Dredge.



J. M. Sz V. E. THORP. DBEDGE.

APPLguATIoN FILED MAY 4, 1909.

Lfl, Patented Mar. 11,1913.

4 SHEETS-SHEET 1.

`witne5ses:

i; 11mm,

J. M.V L V. F.. THORP.

DREDGB.

APPLICATION FILED MAYl. 1909.

Patented Mar.11,1913.

4 SHEETS-SHEET 2` :E l En E... l-

I nventor' J. M. a V. E. THORP.

DREDGE.

AYPLICATION FILED MAY 4,1909,

1,055,37L Patented 1111111119111 l 4 BIEETS--SKBET witnesses: L, inventors J. M. L V. E. THORP.

DREDGE.

APPLIG T1011 PILBD MAYL, 1909.

1,055,3"1 Patented Mar. 11, 1913.

4 SHEETS-SHEET 4.

NlTED STATES rPAJIlBllSl'l OFFICE.

JAMES M. THORP AND VERNOR E. THOR?, OF ALAMEDA, CALIFORNIA.

T all whom t may concern:

Be it known that we, JAMES M. Tnonr and Vniuvon E. Tueur, citizens ot the United States, residing at Alameda, in the county of Alameda and State ot' California., have invented new and useful Improve- `ments in Dredges, of which the following is a specification.

The invention relates to a `machine for dredging and especially to a machine adapted for dredging intermixed ne and coarse material.

Heretofore diticulty has been experienced in the operation of suction dredges in material in which a large percentage of stones or boulders are encountered intermixed with the liner materials, by reason of the tendency of the boulders to lodge or pack in or against the face ot' the suction inlet mouth and obstruct the inflowing current carrying the tineiaanaterial. Devices have heretofore been coustructed to remove such obstructions, but have proven impractical where the boulders form a large percentage of the material to be removed. Under such conditions, the inlet mouth is againv clogged almost immediately after the removal of the previous obstruction. As any obstruction lodging but for an instant in the mouth will reduce the cross-sectional 'area thereof and prevent the proper flow of water into the suction pipe, the .etliciency of the machine is destroyed until' such time as the obstruction is removed by the devices arranged for that purpose. In connection with suction dredges ot "the prior art, it has been proposed to use chain bucket elevators to carry the oversized boulders to the surface, where they are conveyed to any desirable point by other suitable-.means The use oi such elevators is objectionable by reason of their great length and the large'amount of power required for their operation, wliiclrniust be continuous in order to keep the suction mouth clear of obstruction. In material where the percentage ot boulders is small, it is evident that the bucket elevator will perform useful work only at irregular intervals, but nevertheless will require practically the same amount of power for its operation, as would he necessary where the boulders were immerous.

ln the excavating means employed in this invention, it is preferable to use isolated teeth instead f the bucket forms heretofore DREDGE.

Patented Ma r. 'l l 1913.

Serial No. 493.976.

used, as the isolated teeth will enter into the intersticcs between the boulders and dislodge them, while thc broad tat-c of th` bucket forms ridcs over thc boulders, Vtorcthem into "a more secure position.

The object ot' thc present invention is to provide in one vmachine an ell'cctive device to i operate with afhiglrdcgrce ot' elliciency and with the least cxpcnsc in ground of any percentage ot intcrmixturc o't` tine and coarse material.

More particularly stated, the object of the invention is to provide a dredging machine tor the purpose stated, in which the clogging ot the suction inlet mouth is anticipated and prcvcntcd by a scrccn moving in close relation thereto, carryingl away thc oversincd boulders from the path ol thc inlet mouth, but permitting the tincr material to bc drawn thcreinto,

Another objcct is to provide means opcrating intermittently to raise to the surface the oversize bonldcrs only .as they are 'encountered Further objccts ot' thc, invention are to provide improved means for excavating or agitating thc matcrial to bc dredged and mcans for advancing thc excavating devices through such material independent ot the movement ol' the supporting` barge.

lith these and other objects in view, as will more fully hereinafter appear, the invention consists in certain novel 'features of construction and arrangement ot parts hereinafter more l'ully described, illustrated in the accompanying drawings, and particularly pointed out in the claims, it being undei-stood that various changes in the form, size and minor details of the structure may be made without departing from the spirit or sacrificing any ot' thc advantages ot the invention.

Figure 'l is side view ot thc principal parts ot' the invention mounted on a tloat- `ing vessel, the dotted linesl showing the position of thc trame and moving levers in the position of thc greatest backward movement thereof. Fig. '2 is a plan view showing the arrangement otsome of the parts on a tloating vessel, part of the vesselv heilig broken away to show thc trame shifting levers. Fig. 3 is a rear elevation of the lower end o the frame. Fig. 4 is a side elevation of a portion ot' the lower end of the frame showing the hopper, the bucket elevator and means for lowering andraising the hopper gate, the dotted lines showing ,the bucket descended and the gate open. Fig. 5 is a detail of a portion of the bucket and means for holding it to the guides.A Fig G is a side elevationg partly in section of the lower portion or" thi4 frame, showing means for driving the agitating and screening mechanism. Fig. 7 is a section taken through Fig. 6 at :z2-rv. Fig. S is a detailed section of the suction inlet mouth, the end less chain screen, the agitator teeth and means for adjusting the tension on the chain screen. Fifi. 9 is a perspective view otkthe chain screen, showing different forms ot digger teeth.A

r1l`he .devices herein described are usually mounted on a floating vessel or barge A, but they may be placed on tracks, skids or any other foundation suitable to the location, material, or conditions of operation. A well Bn the barge, preferably ot' rectangular :shapev and located on the longitudinal renter 'line thereof is provided toallow the .apparatus to. be lowered to the bed of material to be worked, and also to allpw the material to be raised to the deelt.

The uprights D, arranged at opposite sides of the well B and suitably braced to the deck are provided to carry the groved guides E for the sliding frame G. he guides E are preferably formed of timber, pivoted to the uprights by the pins f2, and extend downward int-o the well l5, the lower ends bearing against the sides thereof and preventing any lateral swaying of the frame G, as the apparatus operates. The guides E are groved to receive the legs ot the T- irons 3, forming the corner members of the frame G which is, preferably formed of triangular section, consisting or 'die 'T-irons 3, the angle iron et and the straps and braces 5 binding the three corner members together to form a light, strong and rigid frame. The T-irons working in the grooves guide the frame in its vertical movement which is accomplished by means ot cables and pulley 8, rectangular in sectien lto accommodate the various devices located at that point. The angle irons 6,.riveted to the angle iron ,/1, are arranged to form a rectangular base and to allow an open passage through the frame :from front to rear, as shown in litigflt The caisson working chamber 8` at the base of the frame contains the necessary mechanism to drive the agitator screen K, indicated in the drawings, las a steam engine. Access is had to the caisson 'through the latter tub'e 9, extending to the upper part orn the frame G and provided on the upper end with an air lock 10 to allow access thereto from the exterior. The forward part 11 of the caisson is open at the bottom 'to allow direct access to 'the bed of material being worked and the air lock is, therefore, necessary to The lower end of the frame G is termed rl`he steam for operating the engine isv formed in a suitable generator' on the decir. oi the barge and conducted to the engine through' the pipe 12, suitably packed, passing through the ladder tube. rlhe exhaust steam passes to the atmosphere through the pipe 13 in the ladder tube.

The longitudinal swinging motion oit the traine (l, by which the agitator screen K is fed into the material to be dredged, is preferably accomplished by the levers 1&15 and the chain drive 1G therefor, although other means can be used to perform this same function. The lever 14 is attached to the trame G at one end and to the cross bar 17 at the other and the lever 15 is attached to the barge Agand also to the cross bar 17. The chain 16 passes across theV deck of the barge, over the drive wh'eel 18 and is fastened to the cross bar 17 underneath the barge by the cables 19. lt will be seen `from the drawings that when the frame Gr is in the backward position, the angle between the levers l1l-15 is smaller than when the frame is in the forward position. Therefore, as the frame starts its forward movement it is evident that it will swing farther for a given displacement of the crossbay 17 than'it will in the forward position for the same displacement. ln other words, for a constant movement of the chain drive 1G, the frame will move faster at the b'eginning of the stroke than it .will at the end thereof. As a corollary thereto, for a constant amount of power applied to the chain, a greater torce will be` exerted on the trame at the end of the swing than at the beginning. In dredging material, this feature is very desirable as it allows a quick movement. of the agitator and excavator over the bed of the stream or water-way being worked, where the deposit is light and easily handled, and a much slower movement at the bank, where the deposit is much greater and more diiiicult to handle. described herein for accomplishing this purpose may fbe varied, as it is evident many other forms of mechanism could be used toperform the same function.

rl`he agitator screen K consists of two endless ,chains 21 formed of links beaning teeth which agitate or excavate the material and chains or cables connecting I said endless chains to 'form a screen. 2l composed ot links and couplings, the links 22 beingprovided at. one end with a The means The endless chain lill) minntion o intensity at v4any The construction .herein inC the closed position.

tion thereof will break and dislodge any pack or jam of smaller boulders that may lodge therein. The axis of the sprocketwheels lies above the inlet mouth 53 so that the side walls thereof are formed by the lower portion of the disk liners v77. During the operation of the machine,V as shown in the drawings, disk liners 7 7 revolve in a clockwise direction, the lower portion adiacent to the suction inlet moving in a direction generally opposite to the direction of the inflowing water. rl`his motion will epel any jam that may form, break it up and allow the material to be drawn into the suction pipe. rlhe side walls of the telescopic flush with the circumferential face of the disk liners 77, forming an inlet mouth with movingr sides and with stationary top and bottom. lt is evident that a small portion ot the undersized boulders will be held with the large boulders on the agitator screen by the force of the suction at'the inlet mouth and will be'carried by the screen away 'from the month. When the screen has traveled a sulicient distance' to remove theforce of suction from the boulders, the smaller ones will fa-ll through the meshes of the screen on account of the vibration thereof., sind be caught by the trough or gutter 55, provided for that purpose, and carried down to the inlet-mouth of the suction pipe.

fit is desirable in some instances to carry the suction 'pipe inlet very close to the point of excavation and also to maintain the full speed. of the intlowing current' without dipoint in the suction pipe. shown and described secures these conditions by Aplacing the inlet mouth in close relation to the cutting implements and by preventing`v the inlet mouth from being clogged, which would reduce the speed of the intlowing current.

The large oversize/boulders whichare retained 'by the screen l are dumped. into the hopper or bin 56 at the rear of the caisson 8 and removed 'therefrom by the bucket 57, 'which is operated by the cable 58 passing over the sheave 59, on the bracket 60. The bucket is guided in its path in the ascending and descending movements by the cables 61 which are engaged by brackets 62 on the bucket` bail 63. At the lower end, the cables 61 areheld by the guides 64 to restrict the motion of the bucket to a. straight path'as it passes the hopper 56. Curved angle-irons 65- are ar, ranged at thgghase as a stopand support for the bucket. 'gThe hopper bin 5K6 is preferably provided with a drop" ate '66 held thereto by the straps and rollers 67, and provided with latches 68 to lock the gate The lugs G9' on the moulth piece 5e are cut awayv posit., the forward nesten descending bucket engage the projection 7G of the latches 68 causing them to rotate about the center 7 1 and disengage themselves from the rollers 72 on the bin. The roller 73 on the latch runs along the face of the 'angle iron 7d holdingthe latch 68 in such position that the lug 69 is held between it and the bracket 75 causing the gate to move in unison with the bucket 57. As the bucket ascends the roller 7 3 on the latch 68 passes over the roller 72 on the bin, thereby securing the latch and allowing the bucket to be raised. A trough or receptacle 50a of any desirable description is arranged on the deck of the barge to receive the boulders as they are brought up and discharged by the bucket.

ln the operation ofthe apparatus, the movement of the agitator vancing levers 14s-A5 and of the bucket hoist are under the control of the operator in the caisson, who being in such close relation to the work, is best able to direct such operations.

:ln gold dredging a large percentage "of the fine gold and rich deposit clings to the bedrock-and is not removed by the agitator screen and suction pipe as they pass over. To lfacilitate the recovery of this rich deend of the caisson is prou vided with an open bottom, so that an operator therein can clean up the surface ot' the bed rock with a hand suction tool. A bulkhead 76 is provided between the open caisson and the engine caisson to prevent the water from owing into the latter compartment when the frame G is at the forward part ot the swing.

When it becomes necessary to repair any ot the working partsoi the apparatus, the frahine G- is raised through the well until the-caisson is above the deck; the frame? may then be tilted vto any desired. angle to ai'l'ord ready access paired.. y

f We claim:

.1.. ln a dredge, the combination of a swinging' trarne, means to swing the frame, and intermediate connecting mechanism adapted to reduce frame. during its forward movement, said intermediate mechanism consisting o the arm 'l5 pivoted to the barge and connected with swinging-means and the arm 14 com necting the arm 15 with the swinging frame.

screen, of the acl-- the rate or" motion. of the to the4 parts to be relio 2. ln a dredge, the combination of averpipe having an inlet mouth at the lower portion thereof, an excavator and conveyor mounted at the lower end of said trame and.

. workin in close relation to the inlet mouth,

means inherent in the conveyingq means for preventing the clogging or the suction inlet, a hopper to receive the material iomthe conveyer and an independently operating bucket elevator to raise the material collected in the hopper. n 1

3. In Y'a'v dredge, the combination of a barge, a vertically adjustable pivoted frame mounted thereon, means for swinging the frame, a suction pipe having an inlet mouth extending from the lower portion of said l frame. agitating and conveying means operating in close relation to the inlet mouth, an endless screen to prevent the coarse material from obstructing the inlet mouth, astorage hopper close to the inlet mouth and arranged to receive the coarse material from the conveying means and an intermittently operating elevator to raise said coarse material to the surface.

4. In a dredge, the combination of a barge, a frame mounted thereon and extending to the material to be dredged, an open bottom chamber atI the lower end of the frame, means for entering the chamber from the barge, means external and in advance of the opening for agitating and removing the material to be dredged and a conveyor above t-he chamber for depositing the coarse material behind the chamber.

5. In a dredge, the combination of a barge, a pendulum frame mounted thereon, a caisson at the lower end thereof having an open bottom, excavating means'external to and in advance of the'caisson, conve ing means above the caisson a hopper be ind the caisson to receive the material -from the conveying means and means within the caisson for driving the excavating and conveying means. Y

6. In a dredge, the combination of a pivoted guide frame, a frame slidable longitu dinally therein,4 a forwardly projecting arm at the lower end of the slidable frame, means arranged on the arm for agitating the material to be dredged and a suction pipe in said forwardly projectin arm having its mouth at the forward en thereof.

7. `In a dredge, the combination of a vertically4 adjustable pendulum frame, a caisson on the lower end of said frame, a forwardly projecting arm attached to the frame above the caisson, and means on the arm for removing large stones from the path of the caisson. g

8. In a dredge, the combination of a barge, a pivoted frame depending therefrom, means to swing the frame comprising a reciprocating element moving at a constantspeed, and means connecting such element to the frame to produce a decreasing rate of motion thereof during the forward stroke.

9.aIn a dredge, the combination of a f barge, a frame supported thereon and dependingtherefrom, a gravity-dumping bin supported at the lower end of said frame, a combined excavator and conveyer supported at the lower end of said frame and arranged to dump into said bin, a bucket, means for raising and lowering said bucket, means for guiding said bucket into position to receive material from said bin, means actuated by said bucket for causing said bin to dump into said bucket, and means for actuating said combined excavator and conveyer.

10. In a dredge, the combination of a barge, a frame supported thereon and depending therefrom, a bin supported at the lower end of said frame, a combined excavator and conveyer supported at the lower Vend of said frame and arranged to dump into, said bin, a bucket, means for raising and lowering saidbucket, means actuated by said bucket for causing said bin to dump into said bucket, and means for actuating said combined excavator and conveyer. JAMES M. THORP. VERNOR E. THOR?. .Witnesses IVM. iK. W'HITE, H. G. Pnosr. 

